In 1988, thanks to the relationship he had built up with Honda throughout the 1987 season with Lotus, and with the approval of McLaren’s number one driver and then-double world champion, Alain Prost, Senna joined the McLaren team. The foundation for a fierce competition between Senna and Prost was laid, culminating in a number of dramatic race incidents between the two over the next five years. At the 1988 Portuguese Grand Prix, Prost made a slightly faster start than Senna but the Brazilian dived into the first corner ahead. Prost responded and went to pass Senna at the end of the first lap. Senna swerved to block Prost, forcing the Frenchman to nearly run into the pitwall at 180 mph (290 km/h). Prost kept his foot down and soon edged Senna into the first corner and started pulling away. Though Prost was angered by Senna’s manoeuvre, the Brazilian got away with a warning from the FIA. Senna would later apologize to Prost for the incident. Ultimately, the pair won 15 of 16 races in the McLaren MP4/4 in 1988 with Senna coming out on top, winning his first Formula One world championship title by taking eight wins to Prost’s seven (Prost had scored more points over the season, but had to drop three second places as only the 11 best scores counted).

1989

Senna driving the McLaren MP4/5 in 1989

The following year, the rivalry between Senna and Prost intensified into numerous battles on the track and a psychological war off it. Tension and mistrust between the two drivers increased when Senna overtook Prost at the restart of the San Marino Grand Prix, a move which Prost claimed violated a pre-race agreement. Senna took an early lead in the championship with victories in San Marino, Monaco, and Mexico. However, unreliability in Phoenix, Canada, France, Britain and Italy, together with collisions in Brazil and Portugal, swung the title in Prost’s favour.

Senna talking to the press in Imola during the 1989 San Marino Grand Prix

Prost took the 1989 world title after a collision with Senna at the Suzuka Circuit in Japan, the penultimate race of the season, which Senna needed to win to remain in contention for the title. Senna had attempted an inside pass on Prost who turned into the corner and cut him off, with the two McLarens finishing up with their wheels interlocked in the Suzuka chicane escape road. Senna then got a push-start from marshals, pitted to replace the damaged nose of his car, and rejoined the race. He took the lead from the Benetton of Alessandro Nannini and went on to finish first, only to be disqualified by the FIA for cutting the chicane after the collision, and for crossing into the pit lane entry (not part of the track). A large fine and temporary suspension of his Super License followed in the winter of 1989 and an irate Senna engaged in a bitter war of words with the FIA and its then President Jean-Marie Balestre. Senna finished the season second with six wins and one second place. Prost left McLaren for rivals Ferrari for the following year.

1990

In 1990, Senna took a commanding lead in the championship with six wins, two second places and three thirds. His most memorable victories were at the opening round in Phoenix, in which he diced for the lead for several laps with a then-unknown Jean Alesi before coming out on top, and at Germany where he fought Benetton driver Alessandro Nannini throughout the race for the win. As the season reached its final quarter however, Alain Prost in his Ferrari rose to the challenge with five wins, including a crucial victory in Spain where he and teammate Nigel Mansell finished 1–2 for the Scuderia. Senna had gone out with a damaged radiator and the gap between Senna and Prost was now reduced to 11 points with two races remaining.

At the penultimate round of the Championship in Japan at Suzuka (the same circuit where Senna and Prost had their collision a year before), Senna took pole ahead of Prost. The pole position in Suzuka was on the right-hand, dirty side of the track. Prost’s Ferrari made a better start and pulled ahead of Senna’s McLaren. At the first turn Senna aggressively kept his inside line, while Prost turned in and the McLaren ploughed into the rear wheel of Prost’s Ferrari at about 270 km/h (170 mph), putting both cars off the track, this time making Senna the Formula 1 world champion. A year later, after taking his third world championship, Senna explained to the press his actions of the previous year in Suzuka. He maintained that prior to qualifying fastest, he had sought and received assurances from race officials that pole position would be changed to the left-hand, clean side of the track, only to find this decision reversed by Jean-Marie Balestre after he had taken pole. Explaining the collision with Prost, Senna said that what he had wanted was to make it clear that he was not going to accept what he perceived as unfair decision making by Balestre, including his disqualification in 1989 and the pole position in 1990.. Senna also testified that no matter what happened he would not yield the corner and that Prost taking his normal racing line (to which the leading driver is entitled to) would result in an accident. Prost would later go on record slamming Senna’s actions as “disgusting” and that he seriously considered retiring from the sport after that incident.

1991

Senna won the 1991 United States Grand Prix in his McLaren MP4/6.

Senna captured his third title in 1991, taking seven wins and staying largely clear of controversy. Prost, due to the downturn in performance at Ferrari, was no longer a serious competitor. Senna won the first four races. By mid-season, Mansell in the more advanced Williams was able to put up a challenge. There were some memorable moments, such as at the Spanish Grand Prix when Senna and Mansell went wheel to wheel with only centimetres to spare, at over 320 km/h (200 mph) down the main straight, a race that the Briton eventually won. Quite a different spectacle was offered following Mansell’s victory in the British Grand Prix at Silverstone. Senna’s car had come to a halt on the final lap but he was not left stranded out on the circuit, as Mansell pulled over on his parade lap and allowed the Brazilian to ride on the Williams side-pod back to the pits. Though Senna’s consistency and the Williams’ unreliability at the beginning of the season gave him an early advantage, Senna insisted that Honda step up their engine development program and demanded further improvements to the car before it was too late. These modifications enabled him to make a late season push and he managed to win three more races to secure the championship, which was settled for good in Japan (yet again) when Mansell (who needed to win), went off at the first corner while running third and beached his Williams-Renault into the gravel trap. Senna finished second, handing the victory to teammate Gerhard Berger at the last corner as a thank-you gesture for his support over the season.

1992

Ayrton Senna driving the McLaren MP4/7A at Monte-Carlo

In 1992, Senna’s determination to win manifested itself in dismay at McLaren’s inability to challenge Williams’ all-conquering FW14B car. McLaren’s new car for the season had several shortcomings. There was delay in getting the new model running (it debuted in the third race of the season, the Brazilian Grand Prix) and in addition to lacking active suspension, the new car suffered from reliability issues, was unpredictable in fast corners, while its Honda V12 engine was no longer the most powerful on the circuit. Senna scored wins in Monaco, Hungary, and Italy that year. During qualifying for the Belgian Grand Prix, French driver Érik Comas crashed heavily and Senna was the first to arrive at the scene. He got out of his car and ran across the track to aid the Frenchman, disregarding his own safety in an effort to aid a fellow driver. He later went to visit Comas in hospital. Senna finished fourth overall in the championship, behind the Williams duo of Mansell and Patrese, and Benetton’s Michael Schumacher.

1993

Senna came from the back of the field to finish fourth at the 1993 German Grand Prix at Hockenheim.

Questions about Senna’s intentions for 1993 lingered throughout 1992, as he did not have a contract with any team by the end of the year. He felt the McLaren cars were less competitive than in previous years (especially after Honda bowed out of Formula 1 at the end of the 1992 season and preseason testing with a Lamborghini V12 unit proved fruitless). Joining Williams alongside Prost (who had secured a drive for the team for 1993) became impossible, since Prost had a clause on his contract vetoing Senna as a team-mate, even though the Brazilian offered to drive for free. An infuriated Senna called Prost a coward in a press conference in Estoril. In December, Senna went to Phoenix, Arizona and tested Emerson Fittipaldi’s Penske IndyCar. McLaren boss Ron Dennis meanwhile was trying to secure a supply of the dominant Renault V10 engine for 1993. When this deal fell through, McLaren was forced to take a customer supply of Ford V8 engines which were two specifications behind that of Ford’s factory team, Benetton. McLaren hoped to make up for the inferior horsepower with mechanical sophistication, including an effective active suspension system. Dennis then finally persuaded Senna to return to McLaren. The Brazilian, however, agreed only to sign up for the first race in South Africa, where he would assess whether McLaren’s equipment was competitive enough for him to put in a good season. After driving McLaren’s 1993 car, Senna concluded that the new car had a surprising potential, albeit the engine was still down on power and would be no match for Prost’s Williams Renault. Senna declined to sign a one-year contract but agreed to drive on a race-by-race basis, eventually staying for the year.

After finishing second in the opening race in South Africa, Senna won in changing conditions in Brazil and Donington. The latter has often been regarded as one of Senna’s greatest victories. He was fifth at the first corner and led the race at the end of the first lap going on to lap the entire field in a race where up to seven pit stops were required by some drivers for rain or slick tyres. Senna then scored a second-place finish in Spain and a record-breaking sixth win at Monaco. After Monaco, the sixth race of the season, Senna unexpectedly led the championship from Prost in the Williams-Renault. As the season progressed, Prost and Damon Hill asserted the superiority of the Williams-Renault car, with Prost securing the drivers’ championship while Hill moved up to second in the standings. Senna concluded the season and his McLaren career with two wins in Japan and Australia, finishing second overall in the championship. The penultimate race was noted for an incident where Jordan’s rookie Eddie Irvine unlapped himself against Senna. The incensed Brazilian later appeared at Jordan’s garage and after a lengthy and heated discussion, punched the Irishman in the face.

In 2010′s “Senna â€“ The Movie”, Alain Prost confesses that he had begun considering his future in Formula One and retirement, half way through the 1993 season when Frank Williams, pressued by Renault, had disclosed to the Frenchman, his desire to hire Senna for 1994. In the movie, Prost reveals that he was displeased of this outcome but also being attacked, especially in his native France, by feelings that Senna was the “poor guy in the slow car” against the might of the faster and more advanced Williams. In response to Frank Williams’ disclosure, Prost immediately decided to retire at the end of 1993 but requested further time before announcing this to Frank Williams. He wanted the backing of the team for the remainder of 1993 to ensure a 4th championship before announcing his decision to retire. Notably, in the 2010 movie titled Senna, this is confused/misrepresented with Prost appearing to not want Senna as a team mate because of a desire to ensure his 4th world championship in a team without Ayrton.